Diagnosis & Testing

Visually inspect the ABS for any damaged or disconnected components or connectors.

Verify that the brake lamps are operational. If they are not, repair them prior to continuing.

Connect the DRB IIIT scan tool to the Data Link Connector located under the instrument panel to the left of the steering column. If the DRB IIIT does not power-up, check the power and ground supplies to the connector.

Turn the ignition key to the ON position. Select ANTILOCK BRAKES.

Read and record any Diagnostic Trouble Codes (DTCs). If any DTCs are present, refer to the appropriate diagnostic information.

NOTE

Diagnostic Trouble Codes (DTCs) are kept in the controller-s memory until either erased by the technician using the DRB IIIT, or erased automatically after 3500 miles or 255 ignition key cycles, whichever occurs first. DTCs are retained by the controller even if the ignition is turned off or the battery is disconnected.

CAUTION

Conditions that result in turning on the amber antilock warning indicator lamp may indicated reduced braking ability.

More than one DTC can be stored at a time. When accessed, the number of occurrences and the
DTC that is stored are displayed.

If no concerns are observed, it may be necessary to road test the vehicle.

Many ABS conditions perceived to be a concern by the driver may be a normal operating condition.

Before road testing a brake complaint vehicle, note whether the red brake warning indicator lamp or the amber antilock warning indicator lamp, or both are turned on. If it is the red brake warning indicator lamp, there is a brake hydraulic problem that must be corrected before driving the vehicle. If the red brake warning indicator lamp is illuminated, there may also be a possibility that there is an ABS problem and the amber antilock warning indicator lamp is not able to illuminate, so the instrument cluster turns on the red brake warning indicator lamp by default. If the amber antilock warning indicator lamp is on; road test the vehicle as described below. While only the amber antilock warning indicator lamp is on, the ABS is not functional. The ability to stop the car using the normal brake system should not be affected.

Turn the key to the OFF position and then back to the ON position. Note whether the amber antilock warning indicator lamp continues to stay on.

If the amber antilock warning indicator lamp stays on, drive the car to a speed of approximately 15
mph (25 km/h) to complete the -ABS Start-Up- and -Drive-Off Cycle.

If at this time the amber antilock warning indicator lamp stays on, refer to the appropriate diagnostic information.

If the amber antilock warning indicator lamp goes out at any time, drive the vehicle a short distance.

Accelerate the vehicle to a speed of at least 40 mph (64 km/h). Bring the vehicle to a complete
stop, braking hard enough to cause the ABS to cycle. Repeat this action several times.

Using the DRB IIIT, read and record any Diagnostic Trouble Codes (DTCs).

If any DTCs are present, refer to the appropriate diagnostic information.